With development of communications technologies, voice call software based on a VoIP (Voice over Internet Protocol) technology has been more widely used. According to the VoIP technology, voice data is encoded and compressed by using a voice compression algorithm, the compressed voice data is packed according to a TCP/IP standard, a data packet is sent to a receive end by using an IP network, and voice data packets are stringed together and decompressed to recover an original voice signal, to transmit voice by using the Internet. By means of the VoIP technology, voice call software can cheaply transmit services such as voice, faxes, videos, and data on an IP network by widely employing an environment of the Internet and global IP-based interconnection, thereby providing more and better services than traditional services and bringing great convenience to users.